More aggressive drug therapy may offer better outcomes for minor stroke patients

Published for the University of Calgary's Hotchkiss Brain Institute.

More aggressive drug therapy may offer better outcomes for minor stroke patients

Stroke is the third leading cause of death in Canada. About half of those strokes are a minor stroke or a transient ischemic attack (TIA). Current treatment guidelines recommend against aggressive treatment with clot-busting drugs for these conditions, but researchers with the Hotchkiss Brain Institute at the Cumming School of Medicine (CSM) believe the guidelines are outdated and are leading a study investigating a new treatment option.

In an international clinical trial researchers are testing a drug called Tenecteplase (TNK). The international trial builds on research already underway at the Foothills Medical Centre. Known as the TEMPO-2 study, researchers have been testing TNK, a drug commonly used to treat patients who have suffered a heart attack, for its effectiveness in reducing disability in patients who have had minor strokes or a TIA and have a blocked blood vessel in the brain. In early findings, TNK is proving to work faster and be safer than the usual clot-busting drug used in stroke called alteplase (tPA – tissue plasminogen activator).

The research team conducts brain scans on patients soon after a minor stroke to check for other blockages. If doctors find a blockage, they can administer TNK, reducing the risk of a future stroke and potentially saving lives.

“About 50 per cent of stroke is relatively minor. So it’s a massive number of patients that we can treat if this trial confirms the benefit of TNK,” says Dr. Shelagh Coutts, a neurologist and the study lead.

Most minor strokes are due to a lack of blood getting to a part of the brain. When this occurs, the person experiences a decreased ability to move a limb or to speak. In some cases, this dysfunction resolves itself — considered a TIA. For those people whose symptoms persist, the condition is considered a minor stroke.

Doctors have been reluctant to use clot-busting drugs on minor stroke and TIA patients because there is a risk of bleeding on the brain, which can be fatal. However, research has shown that minor stroke and TIA patients with evidence of a blocked blood vessel on a brain scan are at a very high risk of being left disabled. Coutts says it is this group of patients that can benefit from aggressive therapy with clot-busting drugs.

In this study, nearly 1,300 patients are being recruited around the world including other cities in Canada, Europe and Australia. If the study shows that TNK is effective for reducing disability in minor stroke or TIA in patients with blocked blood vessels, it will change care of patients throughout the world. The study is expected to take four years to complete.

This research is supported by the Canadian Institutes for Health Research (CIHR).

Other members of the TEMPO-2 research team include Drs. Michael Hill and Mayank Goyal.

Led by the Hotchkiss Brain Institute, Brain and Mental Health is one of six research strategies guiding the University of Calgary toward its Eyes High goals. The strategy provides a unifying direction for brain and mental health research at the university and positions researchers to unlock new discoveries and treatments for brain health in our community. 

The Hotchkiss Brain Institute is a partnership between the University of Calgary and Alberta Health Services.

Dr. Shelagh Coutts is an associate professor in the departments of Clinical NeurosciencesRadiology, and Community Health Sciences and a member of the Hotchkiss Brain Institute at the Cumming School of Medicine.

Dr. Michael Hill is a professor in the departments of Clinical Neurosciences, Community Health Sciences, Medicine and Radiology and a member of the Hotchkiss Brain Institute, the Libin Cardiovascular Institute of Alberta and the O’Brien Institute for Public Health.

Dr. Mayank Goyal is a clinical professor in the Department of Radiology and is a member of the Hotchkiss Brain Institute.